Traffic actuated signaling apparatus



y 5, 1942- J. L. BARKER 2,282,142

TRAFFIC ACTUATED SIGNALING APPARATUS Filed Aug. 8, 1940 A A i z' A f l?E CAM MM INVENTOR BY JOHN L. 5ARKR CZzJQw I.

ATTORNEY Patented May 5, 1942 UNITED STTES PATENT FFICE TRAFFEC ACTUATEDSIGNALING APPARATUS John L. Barker, Norwaik, Conn, assignor to AutomaticSignal Corporation, East Norwalk Conn, a corporation of Delaware Thepresent invention relates generally to traffic control apparatus of thetraific actuated type employed for the control of right of way oftraific at intersections of streets or roads, and in which a trafiicsignal is controlled through a time cycle by a timing mechanism orcontroller in accordance with trafiic actuations of traffic detectors inone or more roads entering the intersection.

The invention relates more particularly to improved traific signalcontrol apparatus of the traffic actuated type for use at one or moreintersections of three roads in which one of the roads at theintersection has relatively little traific compared with the other tworoads but interferes sufilciently with traflic on such other roads torequire a separate right of way period in the traffic signal time cycle.

he invention is also of particular value at one or more of a series ofintersections at which the timing of trailic signals is coordinated topermit progressive movement of trafilc along a main road through theseveral intersections for example, or to provide for simultaneousmovement of main road traffic at all of the series of intersections asan alternative example.

In such coordinated systems the total time length of the signaling cyclemust ordinarily be the same at the several intersections, and at certainintersections having a lightly travelled third road it may be desirableto have the signal normally operated to accord right of Way alternatelyto the two major intersecting roads for appropriate divisions of thetotal cycle and to maintain. right of Way interrupted on the third roadin the absence of traffic in the latter road, but to include in anappropriate part of the same total cycle a right of way period for thethird road in event of arrival of trafilc on the third road.

One type of periodic trafiic signal controller in the prior art employsa si nal switching camshaft of the step-by-step type and a solenoidoperated ratcheting device for stepping the camshaft through its signalcycle, the solenoid being operated momentarily from time to time over anoperating circuit including contacts operated at desired time intervalsby one or more correlated timing devices. In one form of such controllerthe timing device comprises a dial rotated continuously by a synchronousmotor and bearing pins placed at desired spacing around the dial tooperate the solenoid contacts at appropriate time intervals. In suchtype of controller one revolution of the dial determines the total meansconnected with a master controller to resynchronize each dial with themaster controller once per cycle.

In the present embodiment the invention is illustrated in a trafiicsignal controller of the synchronous motor driven continuously rotatingdial type. In accordance with the invention switches controlled by thethird street tramc detector are interposed in the signal controlcircuits extending between the trafiic signals and the step-by-stepcamshaft switches, so that in absence of traffic actuation of thedetector the signal circuits will be completed to certain cam switchesto provide alternate right of way signal periods for two of the threeroads but in response to traffic actuation of the detector the signalcircuits will be completed to certain other cam switches to include aright of Way signal period for the third road in place of a part of theright of way signal period for one of the other two roads.

It is a general object of the invention to provide improved trafilcsignaling apparatus for including an additional right of way signalingperiod, responsive to traific actuation, in a predetermined part of asignaling cycle normally providing a predetermined plurality of right ofway signaling periods in absence of such tram-c actuation.

It is a further object of the inventionto provide improved trafiicsignaling apparatus for an intersection of three roads to include athird right of way Signaling period for the third road, responsive totrafic in the third road, in a predetermined part of a signaling cyclenormally 7 providing two alternate right of Way signaling periods forthe other two roads in absence of trafiic on the third road.

It is also an object of the invention to provide improved trafiicsignaling apparatus for one or more of a group of coordinated traflicsignals to include an. additional right of way signaling period,responsive to traffic actuation, in a signaling cycle normally providinga predetermined plurality of right of way signaling periods in absenceof trafiic actuation, and to provide such additional right of way periodin a part of the same total time cycle in predetermined time relationwith the right of way signaling cycle at one or more of the otherintersections of such coordinated roup.

It is an additional object of the invention to provide improved traificsignaling apparatus for including a third right of way signaling period,responsive to traflic actuation, in a signaling cycle normally providingtwo alternate right of way signaling periods, in which the right of waysignaling cycles are provided by signaling circuits controlled bycamshaft switches and in which additional switches controlled by trafficactuation are interposed in certain of such signaling circuits to selectbetween two sets of cam switches for including and excluding such thirdright of Way period alternatively.

Other objects may appear in the further disclosure and claims herein.

Apparatus embodying the invention will now be described and itsoperation explained in connection with the accompanying drawing.

n the left side of the drawing is represented the intersection I of amain road A, a major cross road C and a minor cross road B, with atraffic signal Z in the intersection and a traffic detector D in the Broad. The usual red, yellow and green colored signal lights CR, CY, CGfor C road, BR, BY, BG for B road and AR, AY, AG

narily referred to, are arranged to face the sev- .1;

eral roads as indicated by the arrows on the signal assembly Z and theseveral signal. lights are also shown schematically in their respectivecircuits in the upper part of the drawing.

It will be appreciated that the several signal lights may be arranged atconvenient points around the intersection instead of in or over thecenter of the intersection as shown at Z.

Above the intersection I and extending to the top of the drawing isillustrated a timing mechanism or controller of the rotating dial typefor the traffic signal Z, with dial Ill rotated by the synchronous motorM.

By means of pins or studs in the rotating disc and a linking arrangementshown herein to be comprised of contacts adapted to be actuated by thepins to energize the solenoid S of a solenoid-operated ratchetingmechanism, a camshaft CS is operated step-by-step through a cycle ofoperation. Contacts operated by cams on the shaft control the display ofsignal indications.

The dial rotates continuously and the several pins operate contacts l3or I4 to step the camshaft CS through the several cam positions, tooperate the several cam contacts 3! through 4| for the signal circuitsas well as the auxiliary control circuit cam contacts 2| through 24. Aseries of contacts or switches 1"! through T9 are interposed between thesignals of A and B roads and their cam contacts, and are controlled byrelay coil R. which in turn is controlled by cam contacts 23 and 24 andby relay DR which in turn is controlled by detector D in the B road.

Sufficient cams and contacts are employed to provide both the two rightof way period signal cycle and the three right of way period signalcycle, the A right of way period in the two period cycle being dividedinto A and 13 right of way periods in the three period cycle.

When trafiic detector D is actuated the relay DR is operated and duringthe next signal cycle relay R. is operated to switch the A and B signalcircuits from the two period cycle cam contacts to the three periodcycle cam contacts, as will be more fully explained subsequently in thisspecification.

At the right side of the drawing another intersection II along the mainroad A is illustrated at a cross road E, and has a signal Z whichprovides also the normal red, yellow and green colored signal lightsdisplayed to A road and E road as indicated by the arrows.

Above the intersection II is shown in the drawing the motor M and dialE0 of a controller for the trafiic signal Z. This controller ispreferably of a type similar to the controller of intersection I exceptthat the controller for II requires only six signal cams and switchesfor six signals AR, AY, AG, ER, EY and EG for the main and cross roadsignals and the solenoid control cam switch 2i, and the trafiic actuatedrelays R and DR and detector D are omitted as it is assumed that theintersection II is of the non-actuated or fixed time type.

The motors M and M for the two intersections are preferably of theself-starting synchronous type connected to the same alternating currentpower supply AC to maintain the respective controller dials i0 and It inpredetermined cyclic relation for progressive traffic movement along themainroad A. Any other controllers of either type at other intersectionsin the coordinated system would be connected to the same AC powersupply.

The construction and operation of an embodiment of the invention in acontroller of the rotating dial type will now be described in moredetail.

The trafiic detector D, in the minor cross road B, is illustratedschematically as a pair of contacts which are adapted to close a circuitbetween wires Qi and 92 responsive to passage of a vehicle over thedetectors for example. Various forms of such trafiic detectors are wellknown in the art such as the pressure contact type in which pressure ofthe vehicle wheel operates the contacts, the magnetic type in whichdisturbance of a magnetic field by a passing vehicle generates a smallelectric voltage to operate relay contacts, the photo-electric type inwhich interruption of a light beam affects a photoelectric cell tooperate relay contacts, and the sound type in which the sound of passingvehicles is detected by a microphone or other sound pickup device tooperate a pair of contacts, for example. It is also well known to usepedestrian push buttons to close the detector circuit 9l-92 as well as avehicle detector. In. each case the relay contacts may be operateddirectly or through an amplifier as needed or desired.

The vehicle detector D is ordinarily located in the side of the road tobe actuated only by vehicles approaching the intersection in road B.

The controller at intersection I for example is of the rotating dial ordisc type and includes a self-starting synchronous type motor M, whichmay be of the general type well known for synchronous electric clocks,for example. The motor M is connected to leads from an AC power source,which is common to all the controllers forming part of the system, fordriving continuously a disc I0 either directly or by a system ofgearing. A plurality of pins or studs H are removably mounted in theface of disc l9 and cooperate with a pair of contacts I3 to close acircuit through the contacts, and another pin l2 also removably mountedin the face of the disc but longer than and independent of pins IIcooperates in similar fashion with the contact pin M.

The disc is preferably provided with a series of holes I near itsperiphery and the pins may be fitted into selected holes as desired todetermine the division of the fixed total time cycle into appropriatesignal periods by stepping the camshaft CS by actuation of the solenoidS. The camshaft CS has an appropriate matching arrangement of cams toprovide the several diiferent signal combinations and the distributionof pin in the continuously rotating disc determines the periods ofdisplay of these several combinations, when the solenoid is connected tobe actuated by the pin operated contacts.

The camshaft CS is carried in suitable bear ings and has mounted on it aplurality of cams EI-I'I for operating signal energizing contacts andcams 5I5 l for operating control circuits. A solenoid S is arranged toadvance the camshaft step-byestep through its cycle by means of aratchet 253 on the camshaft and a pawl M energization and deenergizationof the solenoid moving the camshaft one step. Energizing the solenoidcauses the pawl arm I6, pivoted at ill, to be pulled down against stop72 against tension in spring 2%, causing the pawl 14 to engage anothertooth on ratchet which is prevented from moving backwards by dead pawl25. Subsequent deenergization of solenoid S allows spring It to contractand return arm I6 against stop 73 thus advancing the camshaft counterclockwise one step or tooth in ratchet 28.

Two circuits are provided for energizing the solenoid S. One of thesecircuits includes the pair of contacts I3 which are adapted momentarilyto be closed by each of the pins 1 I in succession as each one of thepins II is rotated through the top of its circular path of movement. Theother circuit includes contact pair I i which is closed once in eachcycle of the disc by the synchronizing pin I2 the purpose of which willsubsequently appear.

The disclosed embodiment of the controller shows an 3 position camshaftand accordingly there are provided '7 pins II for energizing thesolenoid to step the camshaft through all but one of its positions fromwhich one position only the pin I2 and its cooperating contact pair I4are effective to advance the camshaft. Obviously if more camshaftpositions are desired a greater number of pins II are inserted in discI0 keeping the number of pins II always one les than the total number ofcamshaft positions, and corresponding teeth on ratchet 20.

A chart of camshaft positions is included in the lower left portion ofthe drawing and indicates by means of an X in a square that the contacts2 I-24 and 3 I-4I are closed in a particular camshaft position.

In serie with contacts I3 is a pair of contacts 2i which are closed bycam 5I in all positions of the camshaft except position I, which istermed first A Green position AGE, in which pins Ii and contacts I3 arerendered ineifective to advance the camshaft by the opening of contacts2I as shown in the drawing.

In position I only contacts I 4 are effective to close the solenoid Scircuit and contacts M are in position to be operated only by the longpin I2, so that the camshaft CS can be advanced from camshaft one toothor position.

Let us now consider a cycle of operation of the dial and camshaft in theabsence of traflic on road B. Under this assumed condition the operationof cam contacts 22 through 24 for the control circuits will have nosignificance, and the significance of the cam contact 2| in connectionwith contacts I3 has already been explained so that operation only ofthe cam contacts 35 through M for the signal circuits will be consideredin this cycle of operation.

Let it be assumed to start that the camshaft is in position I, signalperiod AGI. in which contacts iii, 32, 38 and ii are closed by cams BI.62,

(i8 and II respectively. Contacts 3! energize the A road green signal AGfrom AC plus power wire Hill via wires I l I and I li, signal AG to ACminus power wire Iill. Contacts 38 energize the B road red signal BRfrom plus wire Ifiil via wires M3 and I 55 to minus wire IElI. Contacts4i energize the C road red signal CR via wire I21 between the plus andminus power wires.

The closed condition of cam contacts 32 in .5: position I has noimmediate significance.

As disclosed above contacts it are ineffective to energize solenoid S inposition I because cam contacts 2I are open but contacts I I areoperated by the synchronizing pin I2 at the end of period AGI toenergize solenoid S momentarily via wires 8%) and ti to advance camshaftCS to position 2. The time the camshaft remains in position 5 depends onthe predetermined constant speed of the dial it and the preselected 1spacing of the pins II and I2.

By reference to the cam chart it will be noted that in the AG2 position2 the contacts 3!, 32, 38 and II remain closed as in position I so thereis no change in signal display.

As dial Id rotates, the next pin II closes contacos I3 to operatesolenoid S momentarly to advance camshaft CS to position 3. In this AYsignal position the cam contacts 3! have opened, but under the assumedcondition of absence of traffic actuation the relay contacts r3 will beclosed and the AG signal will be maintained energized via relay contactsT3 and cam contact 32 which remains closed in this position. Thecontacts 3S and AI remain energized in position 3 as in position 2,continuing display of signals BR and CR.

In position 3 cam contacts 33 are closed but the A yellow signal AY isnot energized thereby because relay contacts T4 are open. Signal AY isconnected via closed relay contacts r5 to wire II 'I and cam contacts 3?but these con.- tacts are open and thus signal AY remains deenergized.

Another pin II next operates contacts I 3 to actuate solenoid S andadvance the camshaft to position 4.

In position cam contacts 32 remain closed and the signal AG remainsenergized over these contacts via relay contacts 13. Cam contacts 38have now opened but since relay contacts rt remain closed in absence oftraffic actuation, the B road red signal BR remains energized over thesecontacts connected directly to plus power. Cam contacts 33 have nowopened again but have no effect as described above.

Also in position 4 the cam contacts 34 and 36 become closed but theseare not efiective to change the signal display since they aredisconnected from the signals by the open relay contacts T6 and Tlrespectively.

As soon as the dial II! has turned sufiiciently for the next pin II toclose contacts I3 momentarily solenoid S is operated to advance camshaftCS into position 5. In this position the signal cam. contacts remain thesame as in position 4.

As soon as another pin II operates contacts I3 the solenoid advances thecamshaft to position t. In this position cam contacts 32 open and thusdeenergize the A green signal AG, since cam contacts are already open.In position 6 the cam contacts 3'! close and energize the A yellowsignal AY via wire I3fi, relay contacts 15 and wire 342.

When dial Ill has turned far enough for the next pin Ii to closecontacts I3 momentarily again the solenoid is again operated andadvances the cam shaft to position I. In this position cam contacts 35close and energize the A red signal AR via wire H and wire I43. Caincontacts 33 also close to energize the B red signal BR over wires H8 andI46 but this signal is already energized over wire I3I, relay contacts13 and wire MI; so that the closure of cam contacts 38 has no immediateefiect. Cam contacts 39 close to energize the C green signal CG overwire Ht; Cam contacts 4i open in position 1 so as to deenergize the Cred signal CR at wire IZI.

As soon as the next pin II operates contacts I3 as a result of furtherrotation of the dial ID, the solenoid is operated again to advance thecam shaft to position 8. In this position cam contacts 35 remain closedto maintain the A red signal AR energized. Cam contacts 39 are now opento deenergize the C green signal CG. Cam contacts All are closed toenergize the C yellow signal CY over wire I20.

The neXt pin II to be operated by rotation of dial iii operates contactsl3 again for the solenoid to advance the cam shaft to position I. Inthis position cam contacts 3| and 32 close, both energizing the A greensignal AG, andcam contacts AI also close to energize signal CR. Camcontacts 34 and 35 both open so as to deenergize signal AR and camcontacts 40 also open to deenergize signal CY.

The cam shaft has now returned to the origi nal position from which thedescription of the cycle of operation was started, under the assumptionthat no traffic actuation of detector D had occurred.

A cycle of operations will now be considered under the assumption that atraffic actuation of detector D in road B has occurred. Actuation ofdetector D closes the contacts of this detector and thus energizes relayDR over a circuit from AC minus wire Iill via wire 92, detector D, wire9!, relay DR and wire 30 to AC plus wire IEO. It will be assumed forexample that the detector actuation occurred in cam shaft position 1.Re-

lay DR will be electrically locked in its energized position by itscontact drl over a circuit from AC minus wire IIII via wire 84, wire 85,cam contacts 22, relay contacts d'rl, wire 9i, relay DR, wire 90 to ACplus. This locking circuit also includes contacts H of relay R inparallel with cam contacts 22.

Since cam contacts 2I are open in cam shaft position I contacts I3 areineffective in this position but as soon as the dial I0 turns so as tooperate contacts I4 by the long pin I2 the solenoid is operated toadvance the cam shaft CS into position 2. The signals remain the same inposition 2 as in position I with the signal AG energized and the signalsBR and CR energized, and all other signals deenergized, just asdescribed in the preceding cycle without trafiic actuation. In thepresent cycle however with traffic actuation, the closure of camcontacts 23 in position 2 now completes a circuit for energizing relay Rfrom AC plus wire I00 via cam contacts 23, wire 86, relay contacts (112,wires 81, 88, relay R, wire 89 to AC minus wire IIlI. Relay R ismaintained energized by a locking circuit from AC plus wire I00 via camcontacts 24, wire 91, relay contacts 12, wire 88, relay R, wire 89, toAC minus, the relay contacts 12 being closed by the initial energizationof relay R. The energization of relay R has also now opened the breakcontacts TI, r3, T5, T9, and has closed its contacts r4, 1'3, H, and r8.

As soon as the dial III has turned sufficiently for the first pin IIafter the pin I2 to actuate contacts I3 the solenoid is operated againto advance the cam shaft to position 3. In this position the camcontacts 23 have opened so that the initial energization circuitdescribed for relay R has now broken but relay R is maintained energizedover the locking circuit described over cam contacts 24. In thisposition 3 the cam contacts 3| open thus deenergizing signal AG sincethe branch circuit for signal AG is also interrupted at the relaycontacts r3, these circuits for signal AG having been previouslydescribed. Cam contacts 33 are closed in this position to energize the Ayellow signal AY via wire H3, relay contacts Y4, and wire I42. Camcontacts 38 and 4| remain closed to energize signals BR and CRrespectively.

As soon as dial I I] has revolved so that the next pin II actuatescontacts I3 the solenoid advances cam shaft CS to position 4. In thisposition cam contacts 33 are open to deenergize signal AY, the branchcircuit for signal AY also being interrupted at relay contacts r5. Camcontacts 38 are also open in this position to deenergize signal BR, thebranch circuit for signal BR being interrupted at the open contacts r9.Cam contacts 34 are closed in this position to energize signal AR viawire H4, relay contacts r6. wire I43. Cam contacts 36 are also closed toenergize signal BG via wire H6, relay contacts 1'1, and wire I44.

In position 4 cam contacts 22 are opened and since relay contacts Tl arealso open the locking circuit of relay DR is broken and this relay isdeenergized in absence of detector actuation at this time. Any momentarytraffic actuations of relay DR during the remainder of the timing periodin cam shaft position 4 will have no permanent effect since relay DR hasno locking circuit at this time. However, this locking circuit isreestablished again by the closure of contacts 22 when the cam shaftshifts from position 4 to position 5 so that any actuation at the end ofposition 4 will be locked in.

As soon as the next pin II operates contacts I3 by rotation of dial Hithe solenoid will advance the cam shaft to position 5, where the camcontacts 22 will be reclosed as just described.

The signal cam contacts remain the same in position as in position 4with the B green signal energized and the A and C red signals energized.

As soon as the next pin operates contacts IS the cam shaft will beadvanced to position 6. In this position cam contacts 32 open but thisdoes not change the condition of signal AG since the circuit connectingwith the cam contacts 32 is interrupted at the open relay contacts r3.Cam contacts 34 remain closed in position 6 so as to maintain signal ARenergized via the closed relay contacts rli. Cam contacts 36 open inposition 6 so as to deenergize signal BG, and cam contacts 3'! close inposition 6 so as to energize the B yellow signal BY via wire H7 and theclosed relay contacts 18, and wire it. Cam contacts 4| remained closedin position 5 to maintain signal CR energized.

When the next pin ii is revolved to operate contacts 13 the cam shaft isadvanced to position 1, in which the signal AR is maintained energizedby continued closure of cam contacts 34. Cam contacts 35 become closedin position. I to establish a branch energization circuit for signal ARvia wire H5. Cam contacts 31 open in position I so as to deenergizesignal BY. Cam contacts 38 close in position I to energize the B redsignal BR via wire H8, wire Hid. Cam contacts 39 also are closed inposition i to energize signal CG.

Upon further rotation of dial it another pin ll operates contacts I3again so as to advance the cam shaft to position 3. In this position camcontacts 34 and 35 remain closed with cam contacts 35 maintaining signalAR energized by direct connection via wire H5 and wire i i-3. Camcontaots 24 open in position 8 so as to break the locking circuit ofrelay R via its contacts 1'2 as previously described, thus deenergizingrelay R and restoring all of its contacts to the positions shown in thedrawing. Cam contacts 39 open in position 8 to deenergize the signal CG.Cam. contacts 38 remain closed to maintain signal BR energized, and anew branch circuit for energiza ion of signal BR is completed by closureof relay contacts r9. Cam contacts 4!) also close to energize signal CY,and cam contacts 4! remain open so that signal CR remains deenergized Assoon as dial it turns far enough for the next pin H to operate contacts13 the cam shaft is advanced to position I, which was the startingposition for this cycle just described. Thus si nals AG and CR arereenergized and signals CY and AR become deenergized. Signal BR remainsenergized via relay contacts 1'9.

Reviewing the two cycles of operation now described it will be observedthat in absence of traffic actuation the relays DR and R were notoperated and therefore the red signal on the B road was maintaineddeenergized throughout the cycle relay contacts T9, the green signal forthe B road maintained deenergized at relay contacts rl' the B roadyellow signal maintained deenergized at relay contacts T8, and that thegreen yellow and red signals for the A road were transferred by relaycontacts r3 to r5 inclusive from one set of cam contacts to another sothat the A road signal remained green through the B road positions t and5 as well as the first A yellow position 3, and that the A yellow signalwas actually energized only in the potential B yellow position 6. Theeffect of all these changes was that the cycle omitted the B road right;of way period and yellow period and continued the A road green period upto the time when the B road yellow period would normally be given atwhich time the A yellow period was substituted.

In the case of the cycle in which traihc actuation occurred, however,the relays DR and R were operated thus changing the signal circuitconnections to the cams in several instances so as to make the B roadgreen signals effective in positions 1 and 5 in place of the red signal,and also to make the A yellow signal effective in position 3 and the Byellow signal effective in position so as to introduce the B road rightof way period in the cycle.

It sh'6uld he noted that if trafiic actuation has not ocurred before theend of the time period in position 2 or prior to this position followingthe last B green position in which the B green signal was displayed, theactuation will not be effective to operate relay R until the followingcycle since the circuit for operation of relay R initially can becompleted only in position 2 via cam contacts 23. It will be notedhowever that if trafiic actuation occurred in position 3 without prioractuation the relay DR. would be locked energized after such actuation,over cam contacts 22 and also over relay contacts H and via relaycontacts drl as previously described. In this case however when the camshaft operates through cam shaft position i and cam contacts 22 areopen, the relay DR is maintained locked in via the closed contact H ofrelay R in the deenergized position of the latter relay. Thus these loc'in circuits assure that the relay R will subsequently be operatedresponsive to any operation of relay DR by traffic actuation, either inthe immediate cycle orin the following cycle, to provide a right of wayperiod for the B road responsive to the B road traffic actuation.

It will be understood that signal color sequences other than that heredisclosed may be used if desired, by appropriate rearrangement of camsor signal circuit connections. For example if it is desired to employoverlapped red signals on all roads or lanes in lieu of a yellow signalin the change signal positions 3, ii and 3 this can be done bylengthening the red signal control came into the preceding change signalpositions or by cross connecting each red signal circuit to itscorresponding preceding yellow signal circuit, and omitting the yellowsignal in each case. Obviously if desired the change signal periodscould be divided into two parts over two adjacent positions by addinganother pin l i for each such division.

Other changes may obviously be made without departing from the spirit ofthe invention as defined by the appended claims.

I claim:

1. In a trains signal controller having a time controlled cyclic switchmechanism and at least three switching positions through which themechanism is operated periodically, three right of way signal circuits,a plurality of switches forming a part of said cyclic switch mechanismincluding three switches operated in sequence in three separatepositions in the cycle of said mechanism and a fourth switch operated intwo of said three positions, relay means operable responsive to trafficactuation and connected to said switch mechanism to be initially sooperated in the first of said three positions of the cycle and to bemaintained operated through the second of said three positions andthereafter released, switches interposed between two of said signalcircuits and the switches of said mechanism and operated by operation ofsaid relay means to disconnect one signal circuit from the fourth switchand to connect a second signal circuit for opera tion by the secondposition switch, and a direct connection between the third signalcircuit and the third position switch and a direct connection betweensaid one signal circuit and the first position switch.

2. In a traffic signal controller having a time controlled cyclic switchmechanism and at least three switching positions through which thecyclic switch mechanism is operated periodically, three right of waysignal circuits, a plurality of switches forming a part of said cyclicswitch mechanism including three switches operated in sequence in threeseparate positions in the cycle of said mechanism and a fourth switchoperated in two of said three positions, relay means oper ableresponsive to trafiic actuation and connected to said switch mechanismto be initialy so operated in the first of said two positions of thecycle and to be maintained operated through the second of said twopositions and thereafter released, switches interposed between two ofsaid right of way signal circuits and the switches or" said mechanismand arranged to connect one signal circuit to the fourth switch and todisconnect a second signal circuit from all switches in the unoperatedcondition of said relay means, and to disconnect said one signal circuitfrom the fourth switch and connect the second right of way signalcircuit to the second position switch in the operated condition of saidrelay means, and direct connections between the third signal circuit andthe third position switch and between i the first signal circuit and thefirst position switch.

3. In a traffic signal controller having a time controlled cyclic switchmechanism and at least three switching positions through which thecyclic switch mechanism is operated periodically, three right of waysignal circuits, a plurality of switches forming a part of said cyclicswitch mechanism including three switches operated in sequence in threeseparate positions in the cycle of said mechanism and a fourth switchoperated in two of said three positions, switches interposed betweencertain of said signal circuits and certain of the switches of saidmechanism, electromagnetc means connected with said cyclic switchmechanism to be operated initially in the first of said two positionsresponsive to traffic actuation and to be maintained operated thereafterthrough said two positions and then to be released, operative connectionbetween said electromagnetic means and said interposed switches toconnect one of said signal circuits to said fourth switch and disconnecta second of said signal circuits from the second position switch whensaid electromagnetic means is not operated, and to disconnect said onecircuit from said fourth switch and connect said second circuit to saidsecond position switch when said electromagnetic means is operated, anddirect connections between said one signal circuit and the firstposition switch and between the third signal circuit and the thirdposition switch.

4. In a traflic signal controller having a time controlled cyclic switchmechanism and at least three switching positions through which themechanism is operated periodically, three right of way signal circuits,a plurality of switches forming a part of said mechanism including threeswitches operated in sequence in three separate positions in the cycleof said mechanism and a fourth switch operated in two of said threepositions, switches interposed between certain of said signal circuitsand certain of the switches of said mechanism, relay means adapted to beoperated by traffic actuation, a second relay means controlled by saidmechanism and by the first relay means to be operated initially in thefirst of said two positions by operation of said first relay means,means to maintain said first relay means so operated after initialoperation in the first and third positions and to maintain it in thesecond position only responsive to non-operation of said second relaymeans and to release it in the second position responsive to operationof said second relay means, means to maintain said second relay meansoperated after initial operation in said first position and through saidsecond position and to release said second relay means thereafter priorto the said first position in the next cycle of said mechanism,operative connec tion between said second relay means and saidinterposed switches to connect one of said signal circuits to saidfourth switch and disconnect a second of said signal circuits from thesecond position switch when said second relay means is not operated, andto disconnect said one circuit from said fourth switch and connect saidsecond circuit to said second position switch when said second relaymeans is operated, and direct con nections between said one circuit andthe first position switch and between the third signal circuit and thethird position switch.

5. In a traffic signal controller having a time controlled cyclic switchmechanism and at least three switching positions through which themechanism is operated periodically, three right of way signal circuits,a plurality of switches forming a part of said cyclic switch mechanismincluding three switches operated in sequence in three separatepositions in the cycle of said mechanism and a fourth switch operated intwo of said three positions, switches interposed between certain of saidsignal circuits and certain of the switches of said mechanism, relaymeans connected with said cyclic switch mechanism to be operatedinitially in the first of said two positions responsive to traificactuation and having make contacts closed only when said relay means isoperated, a second relay means having an operating circuit includinganother switch closed by said mechanism only in the first of saidpositions and one of the make contacts of the first relay means andhaving a holding circuit including a switch closed by said mechanismonly in said first and second positions, said second relay meansincluding make contacts closed only when said relay means is operatedand break contacts opened only when said relay means is operated, aholding circuit for the first relay means including a switch closed bysaid mechanism only in the first and third positions, and a branchholding circuit for said first relay means including a break contact onsaid second relay means, a connection between one of said right of waysignal circuits and said fourth switch of said mechanism via one of saidbreak contacts, connection between a second of said signal circuits andthe second position switch of said mechanism via one ofthe make contactsof said second relay means, and direct connections between the thirdsignal circuit and a third position switch and between said one signalcircuit and a first position switch of said mechanism.

6. In a traffic control apparatus for an intersection of two major roadsand one relatively minor road having right of way signals for theseveral roads, a traiiic actuated device for the minor road only, and acyclic controller operating repeatedly through a cycle of at least threeoperating positions controlling said signals in accordance withactuation and absence of actuation of the trailic actuated device,switches closed by said controller in said three positions respectively,and a fourth switch closed by said controller in the first and secondpositions, a relay connected to be operated by said traffic actuateddevice, a second relay connected to be operated by one of the firstposition switches of said controller responsive to operation of thefirst relay, switches controlled by said second relay, connectionsbetween said right of way signals and said controller switches via theswitches of said second relay for operating the right of way signals forone major road in the first two positions and for the other major roadin the third position respectively of said controller responsive tonon-- operation of said second relay and for operating the right of waysignals for the two major roads in the first and third positions and theright of way signal for the minor road in the second position responsiveto operation of said second relay.

7. In a traffic control apparatus for an intersection of two major roadsand one relatively minor road having right of way signals for the aseveral roads, a trailic actuated device for the minor road only, and acyclic controller operating repeatedly through a cycle of at least threeoperating positions controlling said signals in accordance withactuation and absence of actuation of the traffic actuated device,switches closed by said controller in said three positions respectively,and a fourth switch closed by said controller in the first and secondpositions, a relay connected to be operated by said traffic actuateddevice, a second relay connected to be operated by one of the firstposition switches of said controller responsive to operation of thefirst relay, switches controlled by said second relay, connecticnsbetween said right of way signals and said controller switches via theswitches of said second relay for operating the right of way signals forone major road in the first two positions and for the other major roadin the third position respectively of said controller responsive tonon-operation of said second relay and for operating the right of waysignals for the two major roads in the first and third positions and theright of way signal for the minor road in the second position responsiveto operation of said second relay, and a holding means for said firstrelay connected with the first and third position switches of saidcontroller to maintain said first relay operated in the first and thirdpositions after initial operation by said traflic actuated device andalso connected to be controlled by operation of said second relay torelease said first relay in said second position responsive to operationof said second relay and to maintain said first relay operated throughsaid second position responsive to non-operation of said second relay, aholding means for said second relay to maintain the latter operatedthrough said first and second positions after initial operation andthereafter to release the latter before the first position in the nextcycle.

8. In a trafiic control apparatus for an intersection of two major roadsand one relatively minor road having right of way signals for theseveral roads, a traffic actuated device for the minor road only, and acyclic controller operating repeatedly through a cycle of at least threeoperating positions controlling said signals in accordance withactuation and absence of actuation of the traflic actuated device,switches closed by said controller in said three positions respectively,and a fourth switch closed by said controller in the first and secondpositions, a relay connected to be operated by said trafiic actuateddevice and having make contacts closed only when the relay is operated,a second relay connected to a switch closed by said controller in thefirst position and to one of said make contacts to be operated byclosure of both said switch and said contact and having a holdingcircuit including a switch closed by said controller through the firstand second positions to maintain said second relay operated through thefirst and second positions and to release it thereafter before the firstposition is repeated, make contacts closed only by operation of saidsecond relay and break contacts opened only by operation of said secondrelay, a connection between the right of way signal for the first majorroad and said fourth switch via a break contact of said second relay, aconnection via a make contact of said second relay between the right ofway signal for the minor road and a switch closed by said controller inits second position only, and direct connections between the first majorroad signal and a switch closed by said controller in its first positiononly and between the right of way signal for the second major road and aswitch closed by said controller in its third position only.

9. In a trafiic signal control apparatus for three trafiic lanes havinga cyclic switch controller and a plurality of switches operated therebyperiodically through a cycle of switch operating positions including tworight of way signal positions for the first lane, two right or waysignal positions for the second lane and one right of way signalposition for the third lane all in sequence, relay means operated bytrafilc on the second lane and connected with a controller switch to bemaintained operated in all controller positions except the first rightof way position for said second lane after initial operation by traffic,a second relay means connected to be operated initially by one of saidcontroller switches operable in the second right of way position for thefirst lane responsive to operation of said first relay means andconnected with a controller switch to be maintained operated through thesecond right of way position for the first lane and the two right of waypositions for the second lane after such initial operation, switchescontrolled by said second relay means and connected between the right ofway signals for said first and second lanes and the controller switchesto operate the right of way signal for the first lane in the first fourright of way positions responsive only to non-operation of said secondrelay means and to operate the ri ht of way signal for the second lanein the two right of way positions for the second lane responsive only tooperation of said second relay means, a connection between said firstrelay means and a switch operated by said second relay means in saidfirst right of way position for the second lane to maintain said firstrelay means operated in the last named position responsive only tonon-operation of said second relay means in said last named position,and direct connections between said right of way signal for the firstlane and a controller switch operated in the two right of way positionsfor the first lane and between the right of way signal for the thirdlane and a controller switch operated in the third lane right of wayposition.

10. In a traffic signal control apparatus for three traffic lanes havinga cyclic switch controller and a plurality of switches operated therebyperiodically through a cycle of switch operating positions including tworight of way signal positions for the first lane, two right of waysignal positions for the second lane and one right of way signalposition for the third lane all in sequence, relay means operated bytraffic on the second lane and having make contacts closed by suchoperation, a second relay means connected to a controller switch closedonly in the second right of way position for the first lane and to oneof said make contacts to be operated by closure of both contacts, makecontacts closed only by operation of the second relay means and breakcontacts opened only by operation of the second relay means. a holdingcircuit for the first relay means including a controller switch closedin all positions except the first right of way position for said secondlane and a branch holding circuit for said first relay means including abreak contact of said second relay means, a holding circuit for saidsecond relay means including a controller switch closed in all of saidcontroller positions except the first position for said first lane, adirect connection between the right of way signal for the first lane anda controller switch closed in the first two right of way positions only,a connection between the right of way signal for the first lane and acontroller switch closed in the first four right of Way positions viaone of said break contacts, a connection between the right of way signalfor the second lane and a controller switch closed only in the two rightof way positions for the second lane via one of the make contacts ofsaid second relay, and a direct connection between the right of waysignal for the third lane and a controller switch closed only in theright of way position for the third lane.

11. In a traffic signal control apparatus for three traffic lanes havinga cyclic switch controller and a plurality of switches operated therebythrough a periodic cycle of operating positions including at least oneright of way signaling position and a following signal change positionfor each lane in sequence, a go signal circuit, a stop signal circuitand a change signal circuit for each lane, a traffic actuated device forthe second lane, a first relay means connected to be operated initiallyby actuation of said trafilc actuated device and connected with acontroller switch to be maintained operated in all except one right ofway position for the second lane after such initial operation, a secondrelay means connected to be operated initially by one of said controllerswitches operable in one right of way position for the first laneresponsive to operation of said first relay means and connected with acontroller switch to be maintained operated from said last namedposition through the right of way position for the third lane andthereafter to be released, make contacts closed only by operation ofsaid second relay means and break contacts opened only by suchoperation, a connection between said first relay means and one of saidbreak contacts to maintain said first relay means operated after initialoperation in said one right of way position for said second laneresponsive to non-operation of said second relay means, connections viasaid make contacts between the go and change signal circuits for saidsecond lane and the controller switches operated in the correspondingcontroller positions and between the change signal circuit for saidfirst lane and the corresponding con troller switch and between thefirst lane stop signal circuit and a controller switch operated in allexcept the right of way and change positions for ie first lane,connections via said break contacts between the second lane stop signalcircuit and power supply and between the first lane go signal circuitand a controller switch closed from the first lane right of way positionthrough the second lane right of way position and between the first lanechange signal circuit and the controller switch operated in the changeposition for the second lane, and direct connections between the firstlane go signal circuit and a controller switch operated in the firstlane right of way position and between the first lane stop signalcircuit and a controller switch operated in the third lane right of wayand change positions, and further direct connections between the go,change and stop signal circuits for the third lane and corre spondingcontroller switches therefor.

12. In a traffic signaling apparatus having three right of way signalcircuits, and a cyclic controller having a plurality of switches andoperating said switches periodically through a time cycle normallyproviding two alternate periods for operation of two right of way signalcircuits but also adapted to provide three periods for operation ofthree right of way signal circuits, traffic actuated relay means havingswitches inter posed between certain of said controller switches andcertain of said signal circuits to select between said controllerswitches to include the third right of way period in the cycle in placeof a part of one of the other two periods responsive only to trafiicactuation.

13. In a trafiic signaling apparatus having three right of way signalcircuits, and a cyclic controller having a plurality of switches andoperating said switches periodically through a time cycle normallyproviding two alternate periods for operation of two right of way signalcircuits but also adapted to provide three periods for operation or"three right of way signal circuits, relay means having switchesinterposed between certain of said controller switches and said signalcircuits and operable to select between controller switches to includethe third right of way period in the cycle in place of a part of one ofthe other two periods, relay means for operation by traific actuation,connections between the first mentioned relay means and one of thecontroller switches and the trafdc operated relay means to so operatesaid first mentioned relay means in advance of said part of one periodby operation of said trafiic operated relay means, and holding meanscontrolled by said first mentioned relay means and by one of thecontroller switches to maintain the traffic operated relay meansoperated after trafiic actuation and until said third right of wayperiod has been provided in the cycle.

JOHN L. BARKER.

